That is correct. If your flock carries LL. you should be maintaining a closed flock.
LL is passed to the embryo directly from the hen who laid the egg. This is called "vertical transmission". Most of these embryos die before they hatch. LL virus can also be passed to chicks that hatch from eggs a broody with LL incubates even if they are not ones she laid if her viral load is high and she's shedding it. This happened to me.
As a rule, day-old chicks bought from a hatchery and introduced into an LL flock will acquire resistance during their first few weeks if exposed to very light exposure to the virus. I brood new chicks from day one in my run alongside the adult flock. One year, a gentle old hen adopted a new batch of chicks I was brooding. They were around three to four weeks old when she began covering them at night. It was so sweet and tender at the time.
Unfortunately and unbeknownst to me at the time, she was in a symptomatic state with the virus, soon to die from it, and the chicks were exposed to a lethal viral load as she shed the virus while covering them at night. One chick chose to sleep next to the hen and not under her so she took three years to die of the virus, but the other three acquired symptoms around age five months and died before they were one year old. Lesson learned. I will never permit this again.
LL is passed to the embryo directly from the hen who laid the egg. This is called "vertical transmission". Most of these embryos die before they hatch. LL virus can also be passed to chicks that hatch from eggs a broody with LL incubates even if they are not ones she laid if her viral load is high and she's shedding it. This happened to me.
As a rule, day-old chicks bought from a hatchery and introduced into an LL flock will acquire resistance during their first few weeks if exposed to very light exposure to the virus. I brood new chicks from day one in my run alongside the adult flock. One year, a gentle old hen adopted a new batch of chicks I was brooding. They were around three to four weeks old when she began covering them at night. It was so sweet and tender at the time.
Unfortunately and unbeknownst to me at the time, she was in a symptomatic state with the virus, soon to die from it, and the chicks were exposed to a lethal viral load as she shed the virus while covering them at night. One chick chose to sleep next to the hen and not under her so she took three years to die of the virus, but the other three acquired symptoms around age five months and died before they were one year old. Lesson learned. I will never permit this again.